FARADAY EQUIPMENT

摘要

PURPOSE: To make errors of beam current measurement small by suppressing incidence of ions in a plasma generated in beam plasma and near a mask surface to a Faraday cup. CONSTITUTION: A magnet 30, which generates a magnetic field of a direction crossing an opening part 6 of a mask 4 near an opening part 6, is provided. Magnetic lines of force 32 show the situation of this magnetic field.